Captinjohn ,Thats not a stud,its the nipple for the carbs pump.Im currently looking for a manifold for this engine.I know CH Ignition has a nice one but,its made of plastic .I think im going to design my own type of manifold thats bolts to the flange at the base of the intake port,made from aluminum of course.I will post later when I get around to it.Thanks Captinjohn